Questions tagged [homework]
Homework questions are welcome, as long as they are asked honestly, explain the problem, and show sufficient effort. Please do not use this as the only tag for a question. Please do not add this tag to questions by other people unless they explicitly say that their question is part of their homework.
34
questions
32
votes
4
answers
26k
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Finding unit tangent, normal, and binormal vectors for a given r(t)
For my Calc III class, I need to find $T(t), N(t)$, and $B(t)$ for $t=1, 2$, and $-1$, given $r(t)=\{t,t^2,t^3\}$.
I've got Mathematica, but I've never used it before and I'm not sure how to coerce ...
- 423
3
votes
2
answers
4k
views
Using the epsilon tensor in Mathematica
I'm having a great deal of trouble getting started on a weekly homework assignment in Mathematica. The assignment requires we use the epsilon tensor which is apparently built into Mathematica as ...
- 85
14
votes
8
answers
5k
views
How to make a resizable chess board?
For some reason I need to create a chess board. I can create a chess board by following command:
...
- 547
9
votes
2
answers
607
views
Check homework integration in Mathematica
Given in my homework I have to compute (by hand)
$$\iint\limits_{x^2+y^2\leq 1}(x^2+y^2)\,\mathrm dx\,\,\mathrm dy.$$
My solution so far:
Let $f(x,y)=x^2+y^2$ and $K=\{(x,y)\in\mathbb{R}^2:x^2+y^2\leq ...
0
votes
1
answer
238
views
How do you manipulate this in 2D
Use Manipulate to create an interactive plot that shows the parametrically-defined curve described by {x[t], y[t]} = {t Sin[t], t^2/15} for ...
8
votes
4
answers
1k
views
Generating a polynomial that's accurate to within an error of no more than 1/10^5
I'm currently stuck on a question for class that asks...
"Find a polynomial p[x] that you can use to calculate
6 ArcTan[x]
to ...
- 89
6
votes
4
answers
11k
views
The Lotka-Volterra predator-prey model
I have a Mathematica assignment where we need to numerically solve a Lotka-Volterra predator-prey population equations.
$$\frac{dx}{dt}=ax-bxy,\quad\frac{dy}{dt}=-cx+dxy,$$
where $a,b,c,d\in\mathbb{R}...
- 173
2
votes
2
answers
317
views
2
votes
1
answer
1k
views
Using triangulation
I have been presented with 3 known points and the power densities at those points. I need to use those points to find the location of the actual antenna which is generating the signals.
Power ...
- 51
1
vote
0
answers
316
views
Using a numerical solver to solve a system of ODEs [closed]
Consider the competition model defined by
dx/dt = x (2 − 0.4 x − 0.3 y)
dy/dt = y (1 − 0.1 y − 0.3 x)
Where the population x(t) and y(t) are measured in the thousands and t in years. Use a numerical ...
- 61
0
votes
1
answer
269
views
How to find an equation of a line using Mathematica [duplicate]
(b) Find an equation of the secant line through $ (−2, f(−2)) $ and $ (−1, f(−1)) $. Define this line as $ fs1(x) $ in Mathematica.
- 1
9
votes
3
answers
11k
views
I want to draw a graph using a weighted Adjacency matrix
I have a weighted adjacency matrix as follows:
...
- 201
5
votes
2
answers
174
views
How to find each internal angles of an n-sided irregular polygon
The vectors given in problem are:
p1 = {1, 2, 2};
p2 = {3, 1, 1/4};
p3 = {2, 3, 9/4};
p4 = {5, 2, 0};
p5 = {3/2, 5/4, 19/16};
Find all 5 of the (internal) ...
- 51
4
votes
3
answers
569
views
Area of volume of revolution
I want to calculate the exact area of this volume:
RevolutionPlot3D[
f[x_] = Sqrt[28 x]
, {x, 0, 21}
, Axes -> True
]
Additionally, I wish to see $x$ and $...
- 225
4
votes
2
answers
368
views
How to check whether Laguerre polynomials are orthogonal?
I've got the problem with checking if Laguerre polynomials for n=1,...,10 are orthogonal.
I have to create the list of these polynomials, then create the matrix of integrals from 0 to infinity. ...
- 41
4
votes
1
answer
581
views
How can I make a pretzel shape using Bézier curves?
I am trying to make a pretzel shape,but I cannot seem to get the loops even.
Eventually, I need to make the pretzel shape loop in 3D so I need to nail the 2D concept first. Here's what I have so far....
- 141
3
votes
2
answers
601
views
Plotting the solutions of $y' = -\frac{\cos y}{\sin x}$
I struggle with the problem of plotting the solution of this ODE:
$\qquad y' = -\frac{\cos y}{\sin x}$
I've already tried to use ContourPlot in a loop and in a ...
- 31
3
votes
2
answers
493
views
Tensor contraction
How do I let mathematica compute a tensor contraction like
$\delta_{ab}\delta_{bc}$
with an output
$\delta_{ac}$
efficiently?
I tried TensorContract and TensorReduce but they were not helpful.
...
- 199
3
votes
4
answers
542
views
Print all numbers from a sequence which don't contain the digit 7
so i have this:
Cases[RecurrenceTable[{a[n + 1] == 7 a[n] + n, a[1] == 1}, a, {n, 7}], Except[7]]
But i noticed that it will only exclude numbers that are 7, and ...
- 39
2
votes
2
answers
1k
views
How can I fix my Simpson's rule integration code?
I was tasked with writing a function on Mathematica similar to NIntegrate, but that uses the Composite Simpson's Rule as its method for doing the calculation. The ...
- 23
2
votes
2
answers
438
views
local variable naming & symbolic argument
I'm stuck here with my variable assignment in this scenario
...
- 21
2
votes
3
answers
2k
views
draw part of parabola using graphics
Today, I was doing my physics homework. One of the questions was to draw velocity-time and position-time graphs from the acceleration-time graph. So for the first step I draw acceleration-time using <...
- 289
2
votes
1
answer
559
views
How can I use Histogram and Histogram3D on an image?
I have a .jpg image named r.
I am using the following code to plot a histogram:
...
- 23
2
votes
2
answers
127
views
Inserting an integer into a list while maintaining descending order
Define a function g with two arguments, w and n, where w ...
- 133
1
vote
0
answers
492
views
Calculating double integral bounded by domain in Wolfram Alpha Notebook [closed]
If I want to compute Double Integral on a given region(See attached Picture)
How can I input this on Wolfram Alpha Notebook
- 19
1
vote
2
answers
875
views
Is there a way to select the highest exponent of a polynomial expression?
I have a problem to program a particular kind of expression:
Sum[1/(k n) (HS[t^k,x^k])^n,{n,1,Infinity},{k,1,Infinity}]
where HS[t_,x_] is a polynomial function ...
1
vote
1
answer
801
views
Frequency of elements in a list (merging tally data) [duplicate]
I've got a list in the format of list={{a,1},{a,1},{b,1},{c,1},{b,1}}
And I want it to "compress" into a list of pairs ...
- 137
0
votes
1
answer
936
views
Lagrange Interpolation [duplicate]
I have the following table with 90 elements, and I want to write a loop that gives me the Lagrange operators. I want to construct an interpolation with Lagrange interpolation and show the loop to ...
- 11
0
votes
1
answer
62
views
How do I utilise distance data from a text file?
I've been given a text file which looks like this -
node0, node1 0.04, node8 11.11, node14 72.21
node1, node46 1247.25, node6 20.59, node13 64.94
Where node0 is the first location, and each subsequent ...
0
votes
3
answers
5k
views
Solving One Equation with Two Variables
I am trying to solve an equation with two variables. It is the last step in the process of using the method of undetermined coefficients to solve a nonhomogeneous differential equation. The equation ...
- 101
0
votes
2
answers
1k
views
Least Square Fitting
stuck on a mathematica assignment and could really use some help.
A) Fit a function with the shape log(Y) = a0 + a1log(U) to the datapoints (log(Ui), log(Yi) with an least square fitting. Show this ...
0
votes
2
answers
198
views
Fraction of fibers that have failed
I have the following to set into mathematica.
Assume a stress(sigma) applied on a specimen which has a number of fibers within it. All fibers that have a strength less than the applied stress should ...
0
votes
0
answers
75
views
Function to determine number of trees surviving forest fire [duplicate]
How can I write two functions, each of which have as their argument an array mat of 0s (no trees), 1s (trees), 2s (burning trees), that can determine the trees that survived a forest fire, which run ...
- 337
-2
votes
1
answer
198
views
calling multiple functions in manipulate [closed]
Continuation Manipulate function to generate outliers
I want to call a function in the manipulate environment so that the changing data is fed to another function and both the plots are plotted in a ...
- 113